Interference on 40m

  • 1
  • Question
  • Updated 1 year ago
  • (Edited)
This interference has been going on for over an hour and I am just curious if anyone might know what is the source?
Photo of Ken Davis

Ken Davis

  • 66 Posts
  • 9 Reply Likes

Posted 1 year ago

  • 1
Photo of EA4GLI - 8P9EH - Salvador

EA4GLI - 8P9EH - Salvador

  • 1752 Posts
  • 534 Reply Likes
Looks like DRM (Digital Radio Modiale)
Photo of Ken Davis

Ken Davis

  • 66 Posts
  • 9 Reply Likes
Thanks for the response
Photo of Mark - WS7M

Mark - WS7M

  • 993 Posts
  • 353 Reply Likes
Was it on consistently or did it cycle on/off?  I would suspect a digital mode would cycle on/off.

I have seen something like this here as well and I suspect some man made device near by.
Photo of Ken Davis

Ken Davis

  • 66 Posts
  • 9 Reply Likes
It was on consistently Mark for about 1 hour. The audio was just random hash with slight variation in amplitude. 
Photo of Mark - WS7M

Mark - WS7M

  • 993 Posts
  • 353 Reply Likes
Ok that sounds to me like NOT a digital mode but some power supply or device.  I can't think of any mode where you would want to leave your TX on for an hour.

Unless you have a handheld receiver or a handheld mini-beam and a long coax, kind of hard to track these things down.

I am pretty sure my neighbor across the street has a swamp cooler, a big one and there is some power supply that is putting out little peaks across 10m for me.
Photo of Marty Gibson

Marty Gibson

  • 30 Posts
  • 34 Reply Likes
aircraft radar? old plasma tv.. new neighbours?
Photo of ka7gzr

ka7gzr

  • 215 Posts
  • 36 Reply Likes


Ken,

Have you tried disconnecting all power at the house circuit breaker and running only the Flex? If it goes away of course than its in your house.

Jim

ka7gzr  

Photo of ka7gzr

ka7gzr

  • 215 Posts
  • 36 Reply Likes

Kevin,

Could this be it?

Jim

ka7gzr

Radio Eritrea and Radio Ethiopia Still Battling on 40 Meters

It was a now-familiar story in the July edition of the International Amateur Radio Union Region 1 (IARU R1) Monitoring System (IARUMS) newsletter, which reports that Radio Eritrea and Radio Ethiopia are still slugging it out within the 40-meter amateur band. IARU Region 1 includes Europe, Africa, the Middle East, and northern Asia.

Radio Eritrea and Radio Ethiopia have been active daily on the same 40-meter frequencies. [Wolf Hadel, DK2OM, screenshot]

"The hostile brothers were daily active on 7,150 and 7,175 kHz," said IARUMS Coordinator Wolf Hadel, DK2OM. "Earlier complaints were not regarded. No change." Radio Ethiopia has been deliberately interfering with Radio Eritrea on both frequencies by transmitting white noise, Hadel said.

Elsewhere on 40 meters, Radio Hargaysa in Somalia has been transmitting on 7,120 kHz, and is audible daily in Australia and Japan. On 7,200 kHz, the "Firedrake Jammer" in the People's Republic of China has been transmitting on top of a broadcaster in the Republic of China (Taiwan). The PRC considers Taiwan a province. The Firedrake (or Fire Dragon) jammer, which has been interfering with Amateur Radio signals on 40 and 20 meters over the past decade or longer, also disrupts broadcasts from the Voice of America, Radio Free Asia, and the BBC. The jammer's designation derives from the name of a lengthy Chinese folk tune that the jammer transmits.

So-called "cluster beacons" from Russia have become another issue reported on the 80- and 40-meter CW/digital segments. These CW signals are showing up on several frequencies above 3,590 kHz and in the vicinity of 7,039 kHz and identify with three-letter, R-prefix call signs. They're operated by the Russian Navy, according to IARUMS.

Over the Horizon (OTH) radar signals also continue to intrude on the exclusive Amateur Radio 40-, 20-, 15-, and 10-meter allocations.

Photo of Ken Davis

Ken Davis

  • 66 Posts
  • 9 Reply Likes
I would like to thank everyone for their input. I did power down different items in the house and eliminated that possibility. It did go away that night but not sure when. I am all for blaming it on gremlins, hi hi,
Thanks again.
Ken
W0KRD

Please close this subject.
(Edited)

This conversation is no longer open for comments or replies.